1. Field of the Invention
The present invention relates generally to the field of medical imaging, and, more particularly, to automatic coronary isolation using a n-MIP ray casting technique.
2. Description of the Related Art
Heart disease is a leading cause of death in the United States. One type of heart disease is coronary artery disease. Coronary artery disease is a narrowing or blockage of coronary arteries, which are the arteries that provide the heart with blood. This narrowing or blockage potentially slows blood flow, which decreases the oxygen and nutrients going to the heart. This may lead to chest pain (i.e., angina), or, if one or more of the coronary arteries are completely blocked, a heart attack. Other problems resulting from coronary pathologies include congestive heard failure (hereinafter “CHF”).
Coronary arteries become narrowed or clogged by plaque build-up in the artery walls. Plaque may include excessive cholesterol and other substances in the bloodstream, such as inflammatory cells, proteins and calcium. Plaque build-up in the arteries is called atherosclerosis, which is also known as “hardening of the arteries.”
The early detection of plaque, aneurysms and abnormal configuration of coronary arteries is an important factor in the diagnosis and treatment of coronary pathologies. Echocardiography is a leading tool for the detection of plaque, aneurysms and abnormal configuration of coronary arteries. An echocardiogram uses high-frequency sound waves to visualize the anatomy, structure, and function of the heart. Echocardiography disadvantages include low resolution and noise. Generally, it is not possible to visualize coronary arteries in echocardiography.
More recently, computer tomography (“CT”) has increased in popularity in a wide variety of medical diagnosis fields, such as the detection of cancer. CT provides sub-millimetric spatial resolution and low noise level. However, a very limited number of techniques exist for the detection of heart peripheral vessels in CT.
Magnetic Resonance (“MR”) provides the same resolution and low noise level provided by CT, and, additionally, is totally non-invasive. One using MR does not need any contrast agent injection as required by CT. Furthermore, CT uses X-rays, which are potential health risks over long time exposure, while MR uses the body's magnetic field. However, users of pacemakers, aneurysm clips, and other implants cannot use MR.